In mining, various types of oxygen rescue devices are used. Starting the operation, i.e., the preparation of the devices for use, is fairly time-consuming. Starting the devices in most cases is even more delayed by the wrong measures used by people and attributed to the external danger effects, even with the greatest effort and forced calm; this in turn is a serious source of hazard. Therefore, maximum reliability is being sought in the design of rescue apparatus, with the devices being started quickly and simply. Quick starting so far has not been satisfactorily achieved with the known oxygen rescue devices.
With the known types, access to the most important components of the rescue device could be had only in such a way that first the carrying case had to be opened with a composite series of motions, and only then could, for example, the valve of the oxygen bottle be opened with another motion. Because of the complicated series of motions, the device could not be started without a thought process, with a single instinctive motion, even though it would have been desirable because of the tense psychological condition of the escaping person.
During escape (from danger) with the known rescue devices, besides the constant metering, either oxygen metering controlled by an automatic regulator unit or extra-oxygen metering should be added to ensure rescue. The physical and pyschological condition of the escaping person is strongly influenced by the mode of operation of the rescue device, or by the air quantity obtained from the device and suitable for resuscitation. During escape, the oxygen consumption increases considerably because of the hasty movement.
So far there has not been developed such an oxygen metering system for rescue devices to assure the greatly fluctuating oxygen requirement of the escaping person exposed to heavy physical stress in a suitable manner.